struct point
{
	double x,y;
	point (double, double);
	point ();
	bool operator != (const point&);
	bool operator == (const point&);
	bool operator < (const point&);
};

double sqrhypot(const point& a, const point& b)
{
	return (a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y);
}

struct circle
{
	std::vector <point> bound;

	circle (const point&);
	circle (const point&, const point&);
	circle (const point&, const point&, const point&);
};

